Methods for producing silicon substrates are known from the related art in different developments. Material properties of silicon are generally brought about by diffusion of foreign atoms into the silicon, starting from the surface of the substrate. In this case, a doping substance is deposited on the substrate surface, for example, and is then thermally run into the silicon at very high temperature. This means that the doping substances are stimulated to diffuse into the silicon.
Furthermore, a method for doping a crystalline substrate is discussed in EP 0 750 058 B1, in which first of all a first layer is generated on the substrate which has defects. Subsequently, a second layer is applied on top of the first layer which is separate from the first layer. The second layer contains doping substance atoms which are stimulated to diffuse into the first defective layer, and to occupy the defects in the first layer. The second layer is then removed.
Such methods, however, have the disadvantage that the diffusion processes take place only very slowly, even at very high temperatures. That is why, using such methods, foreign atoms are only able to be inserted into the silicon at depths of at most 20 to 25 μm. Furthermore, there are also foreign atoms, such as antimony (Sb) or germanium (Ge), which diffuse only very slowly, because of their large atomic diameter. Consequently, a sufficient depth of diffusion cannot be achieved within economically justifiable times.